Abstract: A method for producing an iron base material having a coating includes forming a Ni—Cr—Si corrosion-resistant alloy coating film by a combination of composite plate processing with a Ni solution containing Cr and Si, and a heat treatment after the composite plate processing, wherein the Ni—Cr—Si corrosion-resistant film contains Ni, Cr, and Si, and wherein a content ratio of Cr is 1 to 50 wt % of the alloy coating film, a content ratio of Si is 0.1 to 30 wt % of the alloy coating film, and the alloy coating film has a thickness of 0.1 to 1000 ?m, the composite plate processing forms a composite plating film, in which a chromium silicide particle selected from Cr3Si, Cr5Si3, Cr3Si2, CrSi and CrSi2 is co-deposited in a Ni matrix, and the heat treatment at 600° C. or higher decomposes and solid-solubilizes 50% or more of the chromium silicide particle in the Ni matrix.

Abstract: The electrolysis solution for electrolytic ceramic coating includes water, a water-soluble zirconium compound, a complexing agent, carbonate ion, and at least one member selected from the group consisting of an alkali metal ion, ammonium ion and an organic alkali. Te zirconium compound is included at a concentration (X) in terms of zirconium of 0.0001 to 1 mol/L, the complexing agent is included at a concentration (Y) of 0.0001 to 0.3 mol/L, the carbonate ion is included at a concentration (Z) of 0.0002 to 4 mol/L, a ratio of the concentration (Y) of the complexing agent to the concentration (X) in terms of zirconium (Y/X) is at least 0.01, a ratio of the concentration (Z) of the carbonate ion to the concentration (X) in terms of zirconium (Z/X) is at least 2.5, and the electrolysis solution has an electrical conductivity of 0.2 to 20 S/m.

Abstract: A highly corrosion-resistant alloy coating film on the surface of a metallic material by a low-cost and mass-producible simple formation method including forming a corrosion-resistant alloy coating film on the surface of a metallic material, the film contains Ni, Cr, and Si as essential constituents, in which the content ratio of Cr is 1 to 50 wt %, the content ratio of Si is 0.1 to 30 wt %, and the film has a thickness of 0.1 to 1000 ?m.

Abstract: An aluminum alloy member includes a main body including an aluminum alloy serving as a base material, and an electrolytic oxidation ceramic coating coated at a portion of a surface of the main body and including a most outer layer and an inner layer which is arranged close to the main body relative to the most outer layer, the inner layer in which an aluminum oxide is richer than the most outer layer, the most outer layer in which a volume of a titanium oxide or a total volume of the titanium oxide and a zirconium oxide is richer than the inner surface.

Abstract: An aluminum alloy member includes a main body including an aluminum alloy serving as a base material, and an electrolytic oxidation ceramic coating coated at a portion of a surface of the main body and including a most outer layer and an inner layer which is arranged close to the main body relative to the most outer layer, the inner layer in which an aluminum oxide is richer than the most outer layer, the most outer layer in which a volume of a titanium oxide or a total volume of the titanium oxide and a zirconium oxide is richer than the inner surface.

Abstract: A process for duplex heat treatment of combined nitriding treatment and induction quenching treatment on an iron and steel material includes a chemical conversion treatment step for forming a chemical conversion film on a nitrogen compound layer formed on the iron and steel material by the nitriding treatment, after the nitriding treatment and before the induction quenching treatment. A compound layer formed on a surface of an iron and steel material by nitriding treatment is prevented from being oxidized by induction quenching, so that unevenness in film thickness between different portions of an oxidization-inhibiting film does not easily occur, with the result that a nitrogen-containing compound layer obtained after high-frequency heating remain uniformly.

Abstract: The electrolysis solution for electrolytic ceramic coating includes water, a water-soluble zirconium compound, a complexing agent, carbonate ion, and at least one member selected from the group consisting of an alkali metal ion, ammonium ion and an organic alkali. Te zirconium compound is included at a concentration (X) in terms of zirconium of 0.0001 to 1 mol/L, the complexing agent is included at a concentration (Y) of 0.0001 to 0.3 mol/L, the carbonate ion is included at a concentration (Z) of 0.0002 to 4 mol/L, a ratio of the concentration (Y) of the complexing agent to the concentration (X) in terms of zirconium (Y/X) is at least 0.01, a ratio of the concentration (Z) of the carbonate ion to the concentration (X) in terms of zirconium (Z/X) is at least 2.5, and the electrolysis solution has an electrical conductivity of 0.2 to 20 S/m.

Abstract: An oil pump has: a base part having a working chamber; and a rotor provided rotatably in the working chamber. The base part is configured by a plurality of split bodies. At least one of the plurality of split bodies is made of aluminum alloy, and on which an opposed sliding surface made of a ceramic film is formed. The ceramic film of the opposed sliding surface has a hardness of approximately Hv 500 to 1100 and a surface roughness of approximately 2 to 8 micrometers, and contains ?-alumina and zirconia.

Abstract: An aluminum alloy member includes a main body including an aluminum alloy serving as a base material, and an electrolytic oxidation ceramic coating coated at a portion of a surface of the main body and including a most outer layer and an inner layer which is arranged close to the main body relative to the most outer layer, the inner layer in which an aluminum oxide is richer than the most outer layer, the most outer layer in which a volume of a titanium oxide or a total volume of the titanium oxide and a zirconium oxide is richer than the inner surface.

Abstract: This invention provides a method for coating a ceramic film on a metal, which can form dense films on various bases of metals such as magnesium alloys. The formed ceramic film has excellent abrasion resistance, causes no significant attack against a counter material, and has excellent corrosion resistance. The method comprises electrolyzing a metallic base in an electrolysis solution using the metallic base as a working electrode while causing glow discharge and/or arc discharge on the surface of the metallic base to form a ceramic film on the surface of the metallic base. The electrolysis solution contains zirconium oxide particles having an average diameter of not more than 1 ?m, satisfies the following formulae (1) to (3): 0.05 g/L?X?500 g/L (1), 0 g/L?Y?500 g/L (2), and 0?Y/X?10 (3); and has a pH value of not less than pH 7.0.

Abstract: An oil pump has: a base part having a working chamber; and a rotor provided rotatably in the working chamber. The base part is configured by a plurality of split bodies. At least one of the plurality of split bodies is made of aluminum alloy, and on which an opposed sliding surface made of a ceramic film is formed. The ceramic film of the opposed sliding surface has a hardness of approximately Hv 500 to 1100 and a surface roughness of approximately 2 to 8 micrometers, and contains ?-alumina and zirconia.